Understanding Foam in Water Treatment Plants: Causes & Contaminants

Water is a resource which needs cleaning before distribution for human consumption. At times, the water at a treatment plant will gather foam.

Foaming Agents

• Water is treated at a municipal facility prior to being distributed to towns and cities. At times, foam will gather on the basins. The cause of this foam is most likely surfactants. According to the Office of Water Programs Water Treatment Plant Operations manual, the secondary maximum contamination level for foaming agents is 0.5 mg/L.

Levels

• The Water Treatment Plant Operations manual also states that at levels greater than 1.0 mg/L, frothing and foaming occur, which are associated with contamination. At levels less than 1.0 mg/L, there will be an unpleasant taste, such as a fishy, oily or perfume taste.

Prevention

• The main culprits of surfactants and foaming agents come from households and industries. Soaps and cleaners are considered surfactants and should not be poured into drain lines. The drain lines lead to the water treatment plant.